Bell has said that CraveTV is available to all TV providers. It is Shaw and Rogers choice not to offer the service - they probably never will since they treat it as competition to the shomi service, which they own.
The price to subscribe to CraveTV directly is $7.99 - the reason you don't subscribe through your TV provider (if you have one) doesn't matter.
EDIT: I see TorontoColin also responded. I think CraveTV offers the service at a wholesale price to the TV providers and the providers can sell the service at whatever price they choose, just like linear TV channels.